Abstract: An apparatus for detecting topographic variations on an object such as a finger includes an array of sensing elements disposed on a substrate which each have a parasitic capacitance. An insulating receiving surface is disposed over the array of sensing elements and is adapted to receive the object such that a sensing element and a portion of the object located thereabove creates a measurable change in capacitance with respect to the parasitic capacitance. An electronic circuit is coupled to the array of sensing elements for measuring the measurable change in capacitance.

Abstract: A passive liquid crystal display is enhanced by selectively applying low frequency signals to the columns of electrodes on the substrates sandwiching a liquid crystal, selectively applying high frequency signals to the rows of the electrodes so the first and second signals activate the liquid crystal at selected ones of said rows and columns, and passive storing the energy in capacitances exhibited by said rows at the high frequency with an inductor. The low frequency is below the crossover frequency of the liquid crystal, and the high frequency above the crossover frequency.

Abstract: A hand-held device such as a mouse is provided for inputting into a computer relative positional information during movement of the device over a generally planar surface and for inputting an optical image of an object located thereunder. The device includes a housing adapted to be grasped by a user and moved along the surface. A positional transducer is mounted in the housing for generating first signals representative of the amount of movement of the device over the surface. An area imager is located within the housing for recording an image of an object and for generating second signals representative of the image.

Abstract: A single-polysilicon active pixel, methods for operating and making same, and an imaging device employing same are disclosed. The single-polysilicon active pixel comprises a photo site located on a substrate for generating and storing charge carriers, the charge carriers being generated from photonic energy incident upon the photo site and semiconductor substrate, a photo gate, a transfer transistor and output and reset electronics. The gate of the transfer transistor and the photo gate are defined in a single layer of polysilicon disposed on the semiconductor substrate. The source of transfer transistor is a doped region of substrate, referred to as a coupling diffusion, which provides the electrical coupling between the photo gate and the transfer transistor. The coupling diffusion allows for the transfer of a signal stored in a photo site under the photo gate to the output electronics for processing. A plurality of such single-polysilicon active pixels can be arranged to form an imaging system.

Abstract: An active pixel image sensor includes an array of pixels arranged in a first group and a second group. The first group may constitute a row and the second group may constitute a column, for example. A first common conductor is coupled to the pixels in the first group for conducting control signals. A second common conductor is coupled to the pixels in the second group for selectively transmitting signals to processing electronics. Each of the pixels includes a plurality of sensing elements that are each configured for capturing a portion of energy from an object to be imaged. At least one of the sensing elements is of a type distinct from another of the sensing elements. For example, one of the sensing elements may be a photogate and another may be a photodiode. An amplifying arrangement is provided for receiving signals from selected ones of the plurality of sensing elements and for selectively providing output signals to the second common conductor.

Abstract: An image of an object, such as message for facsimile transmission, is acquired optically by setting photosensitive cells along a multiplicity of rows and columns of a random access memory to a given value such as 1, exposing the plurality of cells to an image so the cells change electrical values to exposure values, and after a given time, ending the effective exposure by maintaining values in the cells corresponding to the exposure content of the cells. The maintaining involves going in sequence from row to row, and in each row simultaneously reading the cells in the row and, on the basis of the reading, writing refresh values representative of the exposure values back into the read cells of the row, and repeating the row to row sequence cyclically to prevent changes in the cells due to further exposure. The refreshed data is processed by sequentially reading the refresh values of the cells of a column serially from column to column until all the values have been processed.